Some specialized rolling-element bearings, in particular in the form of cylindrical roller bearings, include a window-type cage, in which the cylindrical rollers are disposed. The windows of the cage are formed such that the cylindrical rollers cannot fall radially outwards out of an assembled unit comprised of a bearing inner ring, cage, and cylindrical rollers. For this purpose, the cage bridges each have a slight undercut, which prevents the cylindrical rollers from falling out. Such bearings can be used for example in traction motors in railway applications.
In railway applications, high strength cages made from a special bronze are needed so that the bearing can withstand the large loads occurring during operation without any problems.
However, a disadvantage of bearings of this type is that, as a consequence of the high strength of the cage, it is not possible to disassemble the assembled unit comprised of the bearing inner ring, cage, and cylindrical rollers without first removing the inner ring. That is, only after the inner ring has been removed can the cylindrical rollers be removed from the cage in a radially inward direction so as to be released from the undercut. The reinstallation of a cylindrical roller in the cage pocket is problematic in a corresponding manner.
Even if the cage bridges have a slight undercut, the cylindrical rollers can be removed by radial extraction if, for example, plastic is used as the cage material; the bearing can thus be disassembled, e.g., for inspection purposes. But, such a disassembly is no longer possible in this manner if the cage is made from the above-mentioned high-strength bronze material.
Rather, even with optimal manufacturing tolerances necessitated by the design of the solid cage and its manufacture from high-strength bronze, a non-destructive disassembly and reassembly of such bearing has not been possible.
This problem is especially troublesome if a bearing inspection, —maintenance and/or —repair should take place on site in mobile applications (e.g., railroad cars).